My wife was jumpstarting our 2013 Express 3500 and crossed the wires on the source vehicle. It took her a minute or two before she figured out what she had done, and by then there was some smoke.

I came home about 20 minutes after she had done this, and was surprised that the van started right up with a proper jump start. Everything seemed to be working fine, although there was a smell of melted wires. But after I turned the van off, it hasn't started since. Sometimes the battery will register some power, but not enough to start the van, and 10 seconds later it will be totally dead.

I figure there should have been something in place to protect the electrical system, and perhaps the fusible link(s) burned up to protect the rest of the system. But I don't know where to find them. Does anyone know the location of the fusible links? Any other ideas to get it going again?

 

One fusible link on the positive cable going to the alternator, and one on the positive cable going to the underhood fuseblock. Fusible links are slow acting, and I think are more intended to prevent fires than protecting electronic components. Where did she put the booster cable clamps?

You can try getting your battery tested or swapping for a good one, but modern charging systems and digitally controlled, closed loop feedback circuits involving electronic control modules, the alternator and regulator, and some sensors. Any one or more of them could have been cooked. Diagnosing the problem may require circuit schematics and troubleshooting analysis.

 

If the alternator isn't toast, it will be.